Recent studies of cognitive processes associated with persecutory delusions suggest that such delusions are associated with abnormalities in the processing of information relevant to the self. Attention to positive and negative trait words was studied in subjects suffering from persecutory delusions, matched subjects with depressed mood and normal controls using an emotional Stroop task. Subjects were required to name the ink colours of: (i) meaningless strings of Os, (ii) low self-esteem personal adjectives, (iii) high self-esteem adjectives and (iv) neutral adjectives. subjects were also asked to rate the degree to which they endorsed as self-descriptive these and other personally descriptive adjectives. The subjects with persecutory delusions demonstrated a significantly higher rate of endorsement for positive adjectives than negative adjectives, but showed a marked degree of interference when colour-naming both positive and negative words. The relevance of these findings to a model of persecutory delusions involving the self-concept is discussed.